In an internal combustion engine, a power generation device drives an electricity generator by use of a drive force of the internal combustion engine, and stores the electricity generated by the electricity generator in a battery. In the internal combustion engine, a control device automatically stops the internal combustion engine when an automatic stop condition such as stop of a vehicle is established, and automatically starts the internal combustion engine when an automatic start condition is established during the automatic stop of the internal combustion engine, so as to improve fuel efficiency.
With the control device for the internal combustion engine according to the related art, when the automatic stop condition is established in a state where a residual amount of the battery is low, the electric generation can be stopped by the automatic stop of the internal combustion engine. In this instance, since only discharge is performed by the battery, the residual amount of the battery becomes insufficient. In such a way, if the insufficient state of the residual amount of the battery is continued, a lifetime of the battery may be decreased (deteriorated).
In order to solve the above problem, Patent Document 1 discloses a control device for an internal combustion engine including a current consumption detecting means for detecting a current consumed by electric loads, and when a current consumption integrating value detected by the current consumption detecting means exceeds a setting value, the automatic stop of the internal combustion engine is prohibited. According to the control device of Patent Document 1, in the case where the current consumed from the battery is high, the automatic stop of the internal combustion engine is prohibited and the electricity generator is driven by the internal combustion engine. Thus, it is possible to prevent the residual amount of the battery from becoming excessively lacking.
Patent Document 1: Japanese Patent Application Publication No. 2001-173480A
However, if the battery is discharged continuously in a short time, the battery has a property that deterioration may be facilitated at an earlier stage. Accordingly, the deterioration in the battery may not be prevented only by prohibiting the automatic stop, as disclosed in Patent Document 1.